Sulfur oxides removal system

ABSTRACT

A continuous system is provided for effecting the removal of sulfur oxides from a waste gas stream through the utilization of continuously rotating an acceptor unit, that has a plurality of segmented zones containing an SO2 adsorbent acceptor material, such that at least one segmental zone is always being rotated into the pathway of an SO2 containing waste gas stream while at least one other contacted zone is simultaneously being passed through and into contact with a regeneration stream so as to undergo the removal of sulfur oxides, and a particular embodiment of the system utilizes two stages of rotating beds or units, whereby a first contacted rotating unit serves as a heat exchanger to provide heat regulating exchange with the waste gas stream and the second stage rotating unit serves to effect sulfur oxides removal.

United States Patent [191 Wenner SULFUR OXIDES REMOVAL SYSTEM [75]Inventor: John G. Wenner, Lincolnshire ill.

[73] Assignee: Universal Oil Products Company, Des Plaines. Ill.

[22] Filed: Dec. 17, I973 [2]] Appl. No.: 425,471

Related U.S. Application Data [63] Continuation-impart of Ser. No.239893, March 3|,

1972, Pat. No. 3.780498.

[52] US. Cl. 55/34; 55/73; 55/390 [51] Int. Cl. 30111 53/06 [58] Fieldof Search 55/34 59, 73, 77, 79, 55/390; l65/7, 10; 23/288 E; 60/902,295, 31 l [56] References Cited UNITED STATES PATENTS 3,780.498 I2/l973Wenner a. 55/73 r May 13, 1975 Primary ExaminerCharles N. Hart Attorney,Agent or Firm-James R. Hoatson, Jr.; Phillip T. Liggett; William H.Page, II

[57] ABSTRACT A continuous system is provided for effecting the re movalof sulfur oxides from a waste gas stream through the utilization ofcontinuously rotating an acceptor unit. that has a plurality ofsegmented zones containing an S0 adsorbent acceptor material, such thatat least one segmental zone is always being rotated into the pathway ofan $0 containing waste gas stream while at least one other contactedzone is simultaneously being passed through and into contact with aregeneration stream so as to undergo the removal of sulfur oxides, and aparticular embodiment of the system utilizes two stages of rotating bedsor units, whereby a first contacted rotating unit serves as a heatexchanger to provide heat regulating exchange with the waste gas streamand the second stage rotating unit serves to effect sulfur oxidesremoval.

2 Claims, 6 Drawing Figures SULFUR OXIDES REMOVAL SYSTEM Thisapplication is a continuation-in-part of my previously filed applicationSer. No. 239,893, filed Mar. 3 l l972 and now U.S. Pat. No. 3,780,498.

The present invention relates to a method for continously removingsulfur oxides from a waste gas stream and, more particularly, there isprovided a continuous rotating bed system which can obviate the need ofa swing-bed" operation to effect periodic regeneration of an S adsorbingmaterial.

In a more specific aspect, the present invention provides a rotating bedsystem where two stages of rotating beds are utilized and rotated from acommon axial power source, with a first contacted rotating unit servingas a heat exchanger zone to regulate the temperature of the flue gasstream passing along to a second stage sulfur oxides removal zone.

BACKGROUND OF THE INVENTION The harmful effects to humans and toproperty caused by the discharge of sulfur oxides into the atmospherealong with flue gases, or other waste gas streams, are generally wellknown and need not be discussed herein. In any event, because of theharmful as pects of sulfur oxides, there is a need to provide improved.inexpensive methods and means to treat waste gas streams to remove thesecontaminants. Also, many localities have banned the use of high sulfurcontent fossil fuels unless flue gas treating steps are combined withthe installation.

Actually, sulfur dioxide (S0 and other sulfur oxides can be removed, orhave been removed, from waste gas streams by various processing schemeswhich have included: absorption, adsorption, wet-scrubbing, chemicalreaction with dry acceptors, and related types of techniques. With theuse of sorption beds or with acceptor materials, there is the need tohave a sorption cycle and a desorption or regeneration cycle, which inturn requires the utilization of a swing" reactor, or switch-bedoperation, in order to provide for the continuous treating of a wastegas stream. The switch-bed system, in turn, requires dual chambers andelaborate valving and timing arrangements to provide a suitableoperational unit.

As an alternative to the use of a swing reactor, there can be a movingbed of adsorptive material which can move between a sorption zone and aregeneration zone; however, this type of system can have materialhandling and material attrition problems.

As still another alternative, the present improved system provides thatthe solid sorptive material be maintained in a fixed bed on, or within,a rotating disc or cylinder arrangement such that the solid material isin segmented parts of the rotating bed portion of the unit and thematerial thereby continuously moved alternatively between a waste gasstream and a regeneration stream.

It may be considered a further object and advantage of the presentimproved system to utilize a two-stage rotating bed arrangement where afirst stage bed can be used to add heat or extract useful heat from theincorning contaminated flue gas stream and then pass the suitably heatedstream onto the second stage sulfur oxides adsorbing rotating bed. Thefirst stage bed has heat ex change surface suitable to transfer heat toan air stream, or other gaseous stream. while the second stage bedcontains activated carbon, alumina, zeolitic molecular sieves, copperoxide, or other suitable S0 Contact material that will alternatively besorbing or reacting with S0 and then be subjected to regeneration byrotation into a pathway of steam, nitrogen, carbon dioxide, methane, orother desorbing and/or regenerating gase ous medium.

In a preferred operation, as heretofore noted, there will be anadditional gas permeable rotating bed of heat exchange material that isalso divided into segmental zones and is also maintained in continuousrotation whereby the waste gas stream is first passed through the heatexchange material to effect a heat exchange prior to being passed intothe bed of S0 adsorbent material. There are thus provided two stages ofrotating beds contact material whereby there can be continuous heatexchange and continuous S0 removal and continuous regeneration of the S0contact material. The heat exchange material may be metallic packing,such as screens, tubular members, chevron-type packing, metal meshes andthe like. In other words, any suitable mate rial that can readily takeon heat and then give up the heat to a second gas stream which is toundergo tem perature elevation may be well utilized. Generally, the tworotating bed zones or housings will be in axial alignment and rotateabout a common shaft although, in some embodiments, it may be ofadvantage to have two separate axles which are in longitudinal axialalignment whereby each bed may be rotated separately and at a differentrate of rotation. The axial alignment permits a straight-through flowpath for the waste gas stream for both rotating beds of the system.

Broadly, the present invention may be considered to provide a continuousmethod for simultaneously effecting the adsorption or reaction of sulfuroxides from a waste gas stream and the removal of such retained oxides,which comprises, maintaining the continuous rotation of a gas permeablecylinder-form bed of an S0 adsorbent material that has been divided intosegmental zones by gas barrier means. a gas permeable rotating bed ofheat exchange material being spaced from and utilized in a series flowcombination with said rotating bed of S0 adsorbent material andproviding a segmen tally divided zone of heat exchange material incontinuous rotation and in the flow path of said waste gas streamwhereby such stream is first passed through said heat exchange materialto effect a heating thereof prior to being passed into said bed of S0adsorbent material, passing the waste gas stream from said heat exchangematerial continuously into contact with at least one segmental zone ofsaid bed and recovering from an opposing side of such zone a gas streamwith reduced content of sulfur oxides, at the same time passing aregenerating gas stream through at least one segmental zone which hasaccepted the sulfur oxides on said material to effect the substantialremoval thereof, and continuing the rotation of said bed through saidwaste gas and regenerating streams to effect a continuingdesulfurization operation.

In an improved method of operation, as well as with respect to adifferent embodiment of apparatus, there may be the provision of a purgestream inlet and an opposing purge stream outlet connecting to theopposing cover means for each end face of the rotating bed holding theS0 adsorbent material such that there may be the stripping and purgingof any excess undesired stripping medium left within the contactmaterial prior to its being rotated into position for contact with thesulfur oxides containing stream. For example, steam or nitrogen may beutilized to purge a C0 stripping gas stream from the adsorptive materialafter it rotates through the pathway of the regeneration or strippinggas medium whereby there will be the removal of residual stripping gasand sulfur oxides that may still be present in the material prior to thedcsorhed portion again reaching the pathway of the waste gas stream.

In connection with the heat exchange rotating bed, as well as for therotating bed holding the adsorbent matc rial for sulfur oxides. thereshall be a plurality of suitable radial partitions throughout the depthof each bed in order to provide segmental zones or compartments and topreclude lateral transfer of the gaseous streams throughout thecylinder-form beds. Thus, each bed comprises a plurality of segmentsprecluding lateral transfer from one segment to another but will permitgas flow from one face to another and from an inlet duct to an outletduct which can be placed in lixed opposing positions with respect toeach rotating bed. There shall. of course, he cover plate means or endhousing which will encasc and substantially preclude gas flow throughthe bed except at those zones where there are opposing passageways andduct means to permit longitudinal flow through a rotating bed, Any lealvage of gas flow streams at the zones of passageways and duct means canbe precluded by suitable gasket arrang ments or "bleeilin streams of aseal gas. in other words. suitable peripherally located gas inletarrangements can provide for the bleed-in of steam, nitrogen or othergaseous medium which will, in effect, preclude the outward flow of awaste gas stream or of a stripping or tlcsorhing medium in the presentapplication, the terms S0 sorptive material" or "SO;- adsorptivematerial and 80;, contact material" are used in a generic manner.inasmuch as the bed may be a true adsorptive material or it may comprisea contact material such as copper oxide on a support which will reactwith the SO: and is sometimes referred to as an acceptor" material. Thelatter type of material is thus regenerated by a reducing gas ratherthan being strictly desorhed: thus. the terms regenerating and'tlesorbing are also used generically and/or synonornously herein andshould not be considered limiting in any way.

Reference to he accompanying drawing and the following descriptionthereof will serve to illustrate dia grammatically the present improvedtype of desulfurization operation as well as set forth furtheradvantages from the utiliration of a combined. two stage rotating bedarrangement resulting in a exchange exchange-"desulturization system.

FIG. l of the drawing is a diagrammatically eleva tional view of thepresent improved two stage system with a lower rotating heat exchangebed and an upper rotating belt containing a suil'ur oxides adsorbentmate rial.

Fl(i5. l and 3 of the drawing are partial plan views, as indicated bythe lines 2 2 and 3--3 in HG. 1.

FIG. 4 of the drawing is a partial sectional elevational view through aportion of a gas outlet indicating one means for effecting a sealbetween a cover means at an edge por ion of one of the rotating beds ofthe unit, such as indicated by line 4--4 in FIG. 2.

FIG. 5 provides a partial sectional clcvational view through an edge ofa cover means and an edge of one of the rotating beds of the unit toillustrate the utiliza tion of a bleed stream to preclude the escape ofa gas stream being passed through a rotating bed of the system.

FIG. 6 of the drawing indicates diagrammatically the utilization ofseparate shaft means for the spaced rotatable beds in the multiple bedsystem.

Referring now particularly to FIG. 1 of the drawing, there is indicateda lower rotating housing 1 adapted to retain a gas permeable heattransfer material 2 which in turn shall be retained in a multiplicity ofsegments by reason of the use of a plurality of spaced radial partitions3 (such as shown in FIG. 3), The rotatable bed or housing 1 isconnected, or constructed to rotate, about a suitable axial shaft member4 which in turn is indicated as being supported from an end bearingsupport member 5. There is also indicated an upper rotatable housing 6adapted to retain gas permeable contact material 7. This latter housingis indicated as also connect ing to an extended portion of shaft 4,which, in turn, connects through gear means 8 and 9 to motor means 10such that there is suitable motive power capable of providing for thecontinuous rotation of each of the contact materials 2 and 7 in therespective housing 1 and 6. As an alternative, and as hereinafterdescribed further, there may be separate motor power means for therespective upper and lower housing whereby there may be differentrotational speeds for the two contact beds.

In accordance with the present invention, the lower heat exchange bed,such as 2 in housing 1, will have an inlet duct means ll connective withcover means 12 such that the incoming 50,; containing waste gas streamcan undergo contact with a heat exchange material 2 prior to passinginto a transfer duct 13 and thence into the sulfur oxides adsorbingmaterial 7. For example with an alumina coated with copper oxide as anS0: acceptor material, it may be necessary to heat the flue gas to theorder of about 750 F. Thus, the heat being transferred to the heatconductive material 2 will, through its continuous rotational movement,give up heat to the waste gas prior to its entering material 7. Theheating stream of steam or separate hot flue gases will pass in aseparate gas pathway, such as provided by flow between inlet duct means16 connecting to cover plate means 12 and an opposing gas outlet ductmeans 14 connecting to cover plate means 15. In other words, heated airor other gaseous stream to give up heat can be introduced in a manner topass continuously through one or more segments of the heat conductingmaterial 2 and provide a resulting cooled stream leaving duct 14.

As best shown in FIGS. 1 and 3, a cooled stream can be dischargedthrough duct means 14 after passing through heat exchange material 2 andafter having entered housing I by way of inlet duct 16 while at the sametime a regulated temperature waste gas stream enters inlet duct H topass upwardly through a different set of segmental zones of contactmaterial 2 and leave by way of transfer duct 13 for subsequent flow intothe sulfur oxides adsorbent material 7. As heretofore noted, varioustypes of materials and arrangements can be utilized as the heatadsorbing material 2 within housing 1 and it is not intended to limitthe present invention to any one type of metal or material.

FIG. 3 of the drawing indicates diagrammatically corrugated metal stripsextending longitudinally from one face to the other for housing 1whereby there is an extended surface area contact bed 2 with a minimumof pressure drop for the flue gas stream; however, other types of heatexchange packings may well be utilized.

Referring again to FIG. I of the drawing and to the second stage ofcontact as provided by the rotating housing 6 with contact material 7,the waste gas stream from the heat exchange zone or housing 1 will passby way of duct 13 into bed 7 to be continuously discharged by way ofoutlet duct 18 from cover plate 19 substantially free of sulfur oxides.It should be pointed out, with particular reference to FIG. 2 of thedrawing, that there is a segmental arrangement for the contact material7 in housing by virtue ofa multiplicity of radial partitioning means 20that will provide a compartmented bed 7 arrangement, in turn precludinglateral transfer of a gas flow stream through the bed from one segmentto another, in a manner similar to the arrangement for housing 1. Thesize or transverse area for each of the duct means 13 and 18 at therespective cover plate means 17 and 19 shall be sufficient in each caseto extend over at least one compartment or segment in housing 6containing contact material 7 to result in the waste gas streamcontacting a selected portion of the cylinder-form contact bed 7 as itis continuously rotated through the stream path.

At the same time that the waste gas stream is continuously flowingthrough the contact material 7, there will be a continuous flow of agaseous stripping medium through a different selected segmental portionof the contact material 7 as provided by a gas pathway from a gas inletduct 21 connecting to cover plate means 19 and an opposing outlet ductmeans 22 connecting to cover plate means [7. By reason of the radialpartitioning means 20, the stripping gas stream will, of course, belimited to passage through the one or more segments of bed 7 and housing6 as may be determined by the transverse area of duct means 2| and 22 aswell as the accompanying openings in the cover plate means 19 and 17. Itis not intended to limit the present invention to any one particularstripping gas or regeneration medium, inasmuch as carbon dioxide,nitrogen, steam, or other medium capable of effecting desorption ofsulfur oxides from the adsorbing medium may well be utilized. On theother hand, with a copper oxide acceptor material in beds 7, then theregeneration gas may comprise a reducing agent such as carbon monoxide,hydrogen and/or a light hydrocarbon such as methane.

Where deemed desirable, there also may be utilized an intermediate purgegas stream to be passed longitudinally through bed 7 and housing 6 at alocation with respect to the rotation of bed 7 to follow the strippinggas flow stream, such that residual stripping gas and sulfur oxides can,in turn. be removed from the bed prior to its being again rotated into aposition corre spending with the pathway of the waste gas stream fromtransfer duet l3. Thus, best shown in FIGS. 1 and 2, an additional duct23 connecting with cover plate I9 can provide for the transfer of apurge gas stream through bed 7 and housing 6 to an outlet duct 24extending from cover plate means l7 on the opposing side of housing 6.As with the other ducts connective with housings l and 6, each set ofinlet and outlet ducts should in each case oppose one another in amanner whereby the gaseous flow stream will pass from one face of thehousing to the other in a straight-through, longitudinal manner. Also,the ducts and aecompanying passageway means through the various coverplate means shall. in each instance. be sized to extend over at leastone segmental portion of an adjacent bed such that there is optimum flowthrough at least one segmental portion of each bed for each gaseous flowstream. The size of compartments or segments in the bed, as determinedby the number of radial partitioning means utilized, shall be determinedby the size of a particular rotating bed unit and the quantity ofgaseous medium to be handled for sulfur oxides removal, stripping, heatexchange, etc. Actually, the waste gas stream can pass throughapproximately half of the rotating bed at any one time and the strippingor reducing stream through approximately the other half portion of therotating bed except for intermediate purge zones as may be requiredbetween the adsorption and desorption zones. Similarly, the waste gasstream can flow through approximately half of the heat exchange material2 in the first stage into housing 1 while the heat exchange stream canpass through the approximate other half portion of the contact material2, inasmuch as lateral flow will be precluded by the radial partitioningmeans 3.

In the operation of the two stage system as set forth in my applicationSer. No. 239,893, a high temperature flue gas stream above about 200 F.may be at an excessive temperature to provide optimum sulfur oxidesadsorption in activated carbon, or other material utilized in bed 7, andthe utilization of the heat exchange material 2 in the first stagehousing I can provide a means for reducing the temperature of the fluegas stream to approximately 200 F. or less. In other words, sufficientheat exchange medium 2 will be provided in a housing 6 to lower the fluegas temperature from whatever its elevated temperature might be down tothe level of 200 F. or less. At the same time and in a continuousmanner, air can be heated from the heat conducting material 2 by passageof such air stream through another sector of housing 1, such as by theflow path between an inlet conduit 14 and outlet conduit 16. However, asprovided by the present system, there may also be a heating of the heatexchange material 2 in order to, in turn, provide an increase in thetemperature of the waste gas stream through duct 13 to the S0 acceptormaterial 7. For example, a copper oxide on alumina type material may beheated to the 700850 F. range, while a vanadium pentoxide material maybe in the 600 to about 900 F. range.

It should also be noted that cocurrent flow with respect to contactmaterial 2 is not necessarily required and the flow may well becounter-current with respect to the heated stream entering by way ofduct means 14 to pass in a longitudinal flow path through the heatexchange material into duct 16, in lieu of the reverse flow. In asimilar manner, there may be a reversal of flow with respect toadsorbent material 7 in housing 6, with the sulfur oxides removingstream being introduced by way of conduit 22 and discharged by way ofconduit 21, in lieu of the down flow being indicated in the drawing.

In FIG. 4 of the drawing there is indicated diagrammatically theutilization of a flexible gasket-like seal member 25 between cover platemeans 19 and a top rim or edge portion for housing 6 such that gas flowpassing upwardly through the bed 7 in housing 6 will not escape betweenthe spacing between cover plate member 19 and peripheral edge portion ofhousing 6. The seal member 25 may be made in the manner of an asbestostadpole or may be made of suitable temperature resistant plastic typematerials, such as teflon,

which will minimize fractional resistance when contact ing a rim portionof housing 6. lt is to be noted that sealing means similar to member 25shall be utilized around all exterior peripheral portions of all of thecover plate members, such as l2, l and 17, as well as plate 19, wherebyall principal gas flow streams will be precluded from escaping from therotating bed system. FIG. 4 also indicates the use of a screen member 26over the open-end portions of housing 6 to retain the contact material 7within the plurality of segmented compartments. The size of the screenopenings and the screen gauge will, of course, depend upon the type ofcontact material being utilized in the bed and the flow conditionsencountered from the upward flow of a waste gas stream through the unit,as well as from the stripping gas flow. Although not shown, suitablemate rial retaining screen means may also be utilized on suitable spacedsupport members along a lower portion of the housing 6 to retain thecontact material within the bed 7 and within each of the plurality ofsegmented compartments of the housing 6.

In an alternative arrangement, there is indicated in H0. 5 of thedrawing the utilization of a bleed stream to prevent principal gasstream losses from the unit at zones between the various opposing gasduct means, the cover plate means and the end portions of the rotatinghousings. Specifically, there is indicated diagrammatically theutilization of a bleed stream inlet means 27 connective with aperipheral bleed passageway 28 in cover plate means 19 whereby there canbe a continuous introduction of steam, nitrogen or other inert me diuminto the peripheral space between cover plate 19 and the edge portion ofhousing 6 to result in a prevention of outward flow from a waste streampath to duct 18. In a similar manner. peripheral bleed stream inlets andpassageways around all cover plate means and/or duct means can providefor bleed-in flows to preclude loss of flue gas or air stream flowthrough housing 1, preclude losses with respect to stripping and purgegas stream flows passing through housing 6. It is to be noted that theuse of gasket means and bleed-in stream means are well known systems foreffecting sealing means for this type of apparatus and it is notintended to limit the present two stage system and two stage apparatusarrangement to the utilization of any one sealing means to contain theprincipal gas stream flow paths.

It is believed that by suitable sizing of housings that it is possibleto have housings which rotate at the same speed, whereby both housingscan be connected to a common rotatable shaft 4 or rotated about a shaftmeans at the same rate from a single motive power source. In the eventthat it is desired to have separate rates of rotation for the twodifferent housings then. as indicated in FIG. 6, separate shaft means 4and 4' may be utilized for effecting the movement of the respectivehousings 1 and 6. In other words. shaft means 4 and 4' will haveseparate bearings and support means and sep arate motive power means toeffect the rotation of the respective housings. Further, although notshown. it is within the scope of the present invention to have powermeans adapted to connect with the peripheral portions of the respectiverotating housing means 1 and 6 whereby such housings rotate about axlesor shaft members 4 or separate axle members 4 and 4'. There are variousmethods to construct and support the housing means, as well as the ductmeans in connection therewith, for both the heat exchange bed and sulfuroxides adsorption beds and such construction means will be obvious tothose skilled in the art of building chambers and duct work, In otherwords, it is not intended to limit the present invention to any onemethod of construction or to any particular type of materials inproviding the successive stages of rotating bed contact, i.e., a heatexchange material in a first rotating bed and a sulfur oxides removalmaterial in a next successive rotating bed.

I claim as my invention:

1. A continuous method for simultaneously effecting the adsorption ofsulfur oxides from a waste gas stream and the removal of such oxideswhich comprises maintaining the continuous rotation of a gas permeablecylinder-form bed of a adsorbent material that has been divided intosegmental zones by gas barrier means, a gas permeable rotating bed ofheat exchange material being spaced from and utilized in a series flowcombination with said rotating bed of S0 adsorbent material andproviding a segmentally divided zone of heat exchange material incontinuous rotation and in the flow path of said waste gas streamwhereby such stream is first passed through said heat exchange materialto effect a heating thereof prior to being passed into said bed of S0adsorbent material, passing the waste gas stream from said heat exchangematerial continuously into contact with at least one segmental zone ofsaid bed and recovering from an opposing side of such zone a gas streamwith reduced content of sulfur ox ides, at the same time passing aregenerating gas stream through at least one segmental zone which hasadsorbed sulfur oxides on said material to effect the substantialremoval thereof, passing a high temperature gaseous stream into contactwith said gas permeable rotating bed of heat exchange material through aportion of said rotating bed that is spaced from the pathway of thewaste gas stream whereby the latter is heated and said high temperaturegaseous stream is cooled down from contact with said heat exchangematerial, and continuing the rotation of said bed through said waste gasand regenerating streams to effect a continuing desulfurizationoperation.

2. The continuous method of claim I still further characterized in thatthe speed of the rotating bed of heat exchange material and the quantitythereof is correlated with respect to the temperature and flow rate ofthe waste gas stream to raise its temperature to suit said S0 adsorbentmaterial.

1. A CONTINUOUS METHOD FOR SIMULTANEOUSLY EFFECTING THE ADSORPTION OFSULFUR OXIDES FROM A WASTE GAS STREAM AND THE REMOVAL OF SUCH OXIDESWHICH COMPRISES MAINTAINING THE CONTINUOUS ROTATION OF A GAS PERMEABLECYLINDER-FORM BED OF A SO2 ADSORBENT MATERIAL THAT HAS BEED DIVIDED INTOSEGEMENTAL ZONES BY GAS BARRIER MEANS, A GAS PERMEABLE ROTATING BED OFHEAT EXCHANGE MATERIAL BEING SPACED FROM AND UTILIZED IN A SERIES FLOWCOMBINTION WITH SAID ROTATING BED OF SO2 ADSORBENT MATERIAL ANDPROVIDING A SEGMENTALLY DIVIDED ZONE OF HEAT EXCHANGE MATERIAL INCONTINUOUS ROTATION AND IN THE FLOW PATH OF SAID WASTE GAS STREAMWHEREBY SUCH STREAM IS FIRST PASSED THROUGH SAID HEAT EXCHANGE MATERIALTO EFFECT A HEATING THEREOF PRIOR TO BEING PASSED INTO SAID BED OF SO2ADSORBENT MATERIAL, PASSING THE WASTE GAS STREAM FROM SAID HEAT EXCHANGEMATERIAL CONTINUOUSLY INTO CONTACT WITH AT LEAST ONE SEGMENTAL ZONE OFSAID BED AND RECOVERING FROM AN OPPOSING SIDE OF SUCH ZONE A GAS STREAMWITH REDUCED CONTENT OF SULFUR OXIDES, AT THE SAME TIME PASSING AREGENERATING GAS STREAM THROUGH AT LEAST ONE SEGMENTAL ZONE WHICH HASADSORBED SULFUR OXIDES ON SAID MATERIAL TO EFFECT THE SUBSTANTIALREMOVAL THEREOF, PASSING A HIGH TEMPERATURE GASEOUS STREAM INTO CONTACTWITH SAID GAS PERMEABLE ROTATING BED OF HEAT EXCHANGE MATERIAL THROUGH APORTION OF SAID ROTATING BED THAT IS SPACED FROM THE PATHWAY OF THEWASTE GAS STREAM WHEREBY THE LATTER IS HEATED AND SAID HIGH TEMPERATUREGASEOUS STREAM IS COOLED DOWN FROM CONTACT WITH SAID HEAT EXCHANGEMATERIAL, AND CONTINUING THE ROTATION OF SAID BED THROUGH SAID WASTE GASAND REGENERATING STREAMS TO EFFECT A CONTINUING DESULFURIZATIONOPERATION.
 2. The continuous method of claim 1 still furthercharacterized in that the speed of the rotating bed of heat exchangematerial and the quantity thereof is correlated with respect to thetemperature and flow rate of the waste gas stream to raise itstemperature to suit said SO2 adsorbent material.